To answer the question, at -10F, brakes should be low on your list of worries. 50 below (F) won’t shatter your brakes. It can make your oil so thick that your starter can’t turn over the engine. It can do something bad to your battery (never figured out exactly what, but I’ll accept that cold is way bad for batteries), and can even make keys behave evilly, but it will not shatter your brake pads.
My cite is 3 days of record-breaking -50F, and 20 “cold” (often well below zero but above minus 50F) winters of car ownership, all without ever having shattered brakes, and only not being able to start my car because of cold once (day #1 of 50 below, with a flat tire, in the middle of nowhere, with no plug-in for my block heater).
Just to be clear – a block heater is a small heating element, generally inserted into the place of a freeze plug, in ones engine block. Nowhere near the wheels where it might have any effect on the brake pads. Sorry if that sounds condescending, but today I got to try to explain, to a non-moron, why a squirting a sticky butterfly valve (in a carb) with WD-40 is not a Good Thing, so I’m going out of my way to not assume things.
Anything that is lubricated by oil needs to be handled gingerly when operated in extremely low temperatures. I figure colder than -20C is extremely cold.
Oil gets really thick in these temperatures. I use the lowest viscosity synthetic oil that my owners manual suggests.
Engine and transmission oils will warm up as the engine warms up (5 minutes is usually sufficient warm up for fuel injected cars). The problems are with oils that don’t start to warm up until the components that they lubricate are actually put to use. Differential, transfer case and power steering fluids remain cold until the vehicle actually starts to roll. The first couple of kilometres of driving should be done gently and slowly. Thick oil doesn’t lubricate as well as warm oil and it causes extreme pressure on things like power steering hoses.
I agree that starting an engine is the worst thing that you can do to it. Especially if it’s cold. Those that start a car every 2 or 3 hours just to keep it warm are likely shortening the life of the engine.
Those of us who live farther north understand that winter-time driving can be an ordeal. The most abused and/or neglected item on the family car or truck is probably the car battery, and cold weather makes turning the engine over much more difficult. Oil turns to sludge. It’s actually hot weather that is tough on the standard lead-acid battery but cold weather additionally reduces the effective life of the charge by about half, or cold cranking ampere hours. So it’s four times more force to turn over the engine, and a much weaker battery. All this can make for the unwelcome “click” when we try to start the car below zero. Keeping the car well tuned is important here mainly because it reduces wear and tear on the starter and battery -
It’s important to note that “dead” or under-charged battery will freeze. A frozen battery must not be charged or jump started and is very dangerous to try and do so. Even an unheated garage or roof makes for easier starting - keeping at least some of the warmth from recent use. Warming an engine up by excessive idling just wastes fuel, the recommended practice is to gently drive the car the first few miles, as the lubricants in the drive train and transmission are stiff and balky too. This will warm up the engine much quicker which is where the engine emissions and fuel mileage is best.
Simple. Batteries store electrical energy in chemical form. At lower temperatures, chemical reactions (which release the electricity to start/run your car) slow down. They happen faster at higher temperatures.
I had this happen to me in similiar conditions although I’ll admit that two ancedotes don’t count as data.
I hopped into my Mazda 6 in one frozen morning Jan 2006 to warm up the engine. Once I got the car started, I tapped the gas and heard a muffled “Whump!” underneath the car. Got out to find the oil filter laying in the driveway and my oil pouring into a giant slick.
This isn’t strictly true: there’s nothing special about “living things” that makes them subject to different rules of cooling. The problem is that wind chill is expressed as a temperature, which causes confusion.
The “real” temperature is what everything will cool down to, given enough time. This applies to cars, rocks, exposed human skin, and anything else. Some living things can generate their own heat to keep warm, but that’s a separate process, and often isn’t efficient enough to protect extremities like noses, fingers, and toes.
The “wind chill” is the cooling rate. Everything cools faster in moving air due to convective currents (basically as you warm a bit of air, it’s pulled away). Evaporative cooling (like sweating) has pretty much ceased at any temperature where you’re getting wind chills. The wind chill is the “equivalent” temperature without wind that would give you the same cooling rate (approximately) that the wind does at the real temperature.
So: wind chill indicates how fast something cools, whereas the real temperature indicates the temperature it will cool down to. Since things that stay outside will usually go to ambient (‘real’) and stay there, whereas humans and the like are in real trouble if they start getting anywhere close to ambient, you get the notion that wind chill only affects living beings. But the real difference between inanimate objects and humans isn’t the cooling rate, but the destructiveness of the destination temperature.
I think there is a misconception about the misconception Although factors specific to humans are considered, with one goal being to indicate the danger of frostbite, the primary factor in wind chill is the heat transfer rate due to wind. So although it may be targeted to people, that doesn’t render it meaningless for inanimate objects.
Wind chill *is * meaningful to any inanimate object with a temperature higher than the ambient air temperature. A hot engine block will lose heat faster in wind than still air. That’s why (electric) radiator fans turn on at idle but not at highway speeds.
The common misconception about wind chill is that if the air is 0F but wind chill takes it down to -30F, then inaminate objects will be -30F. But of course, they can never get colder than 0F no matter how hard the wind is blowing.
And, for the record, the ‘wind chill temperature’ is generally a huge exaggeration, as it’s based on a naked person’s cooling rate. Most people don’t hang out naked in temperatures where wind chill is a concern, so their true cooling rate isn’t as bad as the standard ‘wind chill temperature’.
What’s the Straight Dope on installing a piece of cardboard in front of the radiator in Really, Really Cold weather? Some big 18 wheel tractor-trailer rigs have spiffy, zippered vinyl covers too. Wind will definitely speed the rate at which a car engine warms up or cools down!
I had a car that didn’t really heat up much on the highway - big V8, plenty of power, pretty efficient too IIRC about 30 mpg, but used too little power at steady cruising to keep the engine warm. The cardboard allowed it to heat up enough to get some decent heat.
Thank you! Plain english, no unnecessary details, perfectly coherent, correct – thank you thank you thank you!
I have heard 97 very precise technical explanations, all of which were so far over my head they might as well have been speaking Greek. Being the sole Liberal Arts type in a family full of Engineers can be a life long exercise in frustration.
I’ve done this with some success in the past with older cars. Just remember to keep an eye on the temp guage and to remove the material when it gets warmer.
Oil filters are usually steel and the part of the engine they screw on to (from my experience) appears to be aluminum. Is this right Rick?
That would be why we’ve heard stories of filters falling off really cold blocks. The two metals expand at different rates and the filters become loose. I can then envision the oil pressure causing the filter to spin free of the fitting and falling off the car.
This is a review of what others have said but… living 20-odd years in Saskatchewan, I recall doing this stuff in winter:
changing the oil (to something thinner)
putting on the snow tires
plugging the block heater and battery blanket in
adding some gasline antifreeze when filling up
letting the car warm up a bit before driving (like someone said above, often while scraping the windshield)
I found it was a tad hard to shift my old car when it got down to -35 or -40 (or even -50 that one winter), but nothing ever broke. Well, except when I forgot to unplug the car that one morning…
I used to have a little MGA and it ran fine in the SF bay area. When I drove it up to Tahoe, though, the engine wouldn’t put out enough heat to keep the inside warm. When I put cardboard in front of the radiator, it helped a hell of a lot heating the cab, but not perfect. If I recall correctly, I had the radiator covered completely. (Those small 4-bangers didn’t put out much heat!)
Newly installed 10W30 fails cold cranking and flowing tests around -5.
Newly installed 5W30 fails those tests at -25 or so.
Newly installed 0W30 fails those tests at -40 or so.
As an installed crankcase oil ages, its cold-weather performance gets worse.
If he was running 5W30, I can easily see this happenning, especially if he was over-extending his drain intervals or nearing time for his next oil change.
Although factors specific to humans are considered, with one goal being to indicate the danger of frostbite, the primary factor in